True. As long as airline business was highly regulated and/or subsidised BA was profitable. However, is was not a problem to be profitable during those days. There was no need to manage an airline, you just had to operate an airline and had a license to print money.

However, at one day they had to start to manage an airline. And at the latest when starting their German adventure profitablity was no longer true. Could they manage in non (or not so much) regulated markets? No. There are only a few profitable airlines, BA is certainly not one of them.